The section on the document character set addresses the issue of what abstract characters may be part of an HTML document.

文档字符集部分主要讨论哪些抽象字符可以在HTML文档中出现。

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Servers and proxies do not have to serve a document in a character encoding that covers the entire document character set.

服务器以及代理（proxy）无须提供完全编码的文档（即，文档采用涵盖文档全部字符集的编码方式）。

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Servers and proxies do not have to serve a document in a character encoding that covers the entire document character set.

服务器以及代理（proxy）无须提供完全编码的文档（即，文档采用涵盖文档全部字符集的编码方式）。

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